Most American and internationally made automobiles are powered by liquid cooled engines. The operating temperature of the liquid coolant can exceed the boiling point of water, and even when the operating temperature is below the boiling point of water the temperature of the coolant liquid is great enough to cause burn injuries to human flesh upon contact. Conventional liquid cooling systems are typically pressure closed systems such that as the temperature of the liquid coolant increases so does the pressure within the cooling system.
Consequently, there is considerable danger to an automotive serviceperson in removing the cap on the cooling system when the cooling system is at or near its operating temperature. Typically the cap is upon a forwardly placed radiator at a point in the engine compartment which is more or less within the reach of most servicepersons. The temptation during busy work periods to simply reach in and grasp the cap with no hand covering at all or with a slightly bunched rag is great, and yielding to that temptation frequently results in scald burns to the serviceperson from contact with either the liquid or the hot gases escaping under pressure at the instant that the seal of the cap is released. In addition, the radiator cap is often placed in tight surroundings and in close proximity to protruding flanges of various plastic and metal shrouding such that, aside from consideration of the burn hazard, a serviceperson's fingers are often cut in the process of removing and replacing the cap.
Accordingly there is a need for a compact, readily accessible and inexpensive tool which is always within reach of an automotive serviceperson so that the serviceperson will not be tempted to use bare hands or flimsy rags to remove a radiator cap. In addition a single tool should be able to accommodate most, if not all, of the radiator caps which the serviceperson will encounter in typical work situations. The removing tool should be durable and should allow the serviceperson to remove the cap without either touching it bare handed or getting fingers down where they can be cut. In addition the tool should tightly grip the radiator cap so that the serviceperson can control the direction of tilt of the cap at the instant it is loosened from the radiator so that the cap and the tool together form a gas and liquid spray shield to deflect hot gases and liquids away from the serviceperson harmlessly into the engine compartment. Finally the tool should serve to assist in reinstallation of the cap where there is still some burn hazard and the danger of cutting remains the same.
A number of devices are known for assisting the serviceperson in the removal of a hot radiator cap. One device is made of an easily compressible material which grips the cap in much the same fashion as the conventional mason jar lid opener grips the cap of a jar under the compressive force of the user's grip. Another device employs a rigid bell shaped housing with magnets for retaining the cap after it is removed. Other devices are known which are in appearance much like conventional socket wrenches. Most of the devices are designed for particular widths and shapes of radiator caps and do not approach universality of application. One device is known which employs an adjustable leaf spring to clamp different sized radiator caps and those without lugs.
None of the known devices disclose a simple and inexpensive tool for removing, with a single tool, the vast majority of American and internationally made radiator caps. Neither do they provide in their design a means to insure that the fingers of the serviceperson are not near burning or cutting hazards, yet at the same time providing a mechanical gripping surface which allows at least as much leverage to be applied to the cap as could be applied bare-handed. Neither do they provide a gripping and leverage means so designed as to permit the tool to be inserted into the modern crowded engine compartment without interference with shrouding, hoses or other engine compartment equipment.